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Seventy nine bottom sediment samples were collected from Abu Dhabi area from Ghantoout area in the north east from Abu Al Abyad island to determine the regional distribution of concentration of trace metals and pollution levels in the studied area. In general, a negative correlation has been reported between trace metals concentration and total organic matter with the exception of Cu, Zn, Co and Cr. A negative relation between trace metals concentrations and carbonate content was also found in the area of study. The present study focuses on the levels of copper, lead, iron, manganese, nickel, cadmium, zinc and vanadium in order to assess the extent of the environmental pollution and to discuss the origin of these contaminants in the sediments. The average concentrations of copper, zinc, lead, iron, manganese nickel, cadmium and vanadium are 4. 65, 11.94, 1.91, 2800, 92.26, 10.55, 0.082 and 11.43 µg/g respectively. These values are within the permitted levels in the marine activity areas and industrial activity areas, which means that trace metals are not derived from the pollutant sources.

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Thirty two bottom sediment samples were collected from four different areas from Arabian Gulf, United Arab Emirates. These areas include: (a) Dubai, (b) Sharjah, (c) Ajman, and (d) Ras Al-Khaimah. The present study focuses on the levels of copper, lead, iron, manganese nickel, cadmium, zinc and vanadium in order to assess the extent of environmental pollution and to discuss the origin of these contaminants in sediments. Positive correlations are found between increase of heavy metals concentration and decrease of grain size. It is well established that heavy metals tend to be concentrated in the finer grain sizes of bottom sediments of the studied areas. Some large size grain sediments show high heavy metals concentrations due to formation of large agglomerates from the smaller particles enriched by contaminations. The concentrations of copper, zinc, lead, iron, manganese, nickel, cadmium, and vanadium are varied between 5.05, 10.15, 2.82, 3230, 119.0, 16.92, 0.105, and 11.04 µg/g, respectively, which are within the permission levels. This means that the samples containing these metals were derived from nonpollutant sources.

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The ophiolite sequences of UAE, as a part of Oman ophiolite, represent both, mantle section and crustal section. The crustal part of the ophiolite sequences, consists of a layered series (cumulate peridotites and gabbros). This paper aims to overview geochemical character and some mechanical and physical features of the gabbroic rocks. The gabbros comprise troctolite, olivine gabbro, normal gabbro, gabbronorite, and uralitized gabbros. Geochemical features indicate that they are tholeiitic and are formed in an arc-related tectonic setting. On NMORB normalized pattern of gabbros, the HFS-elements (P, Zr, Sm, Ti, and Y) show a flat pattern parallel to NMORB. In contrast, the LIL-elements (Rb, Ba, Th, Sr) are relatively more enriched than NMORB. The enrichment of LIL-elements over the HFS-elements and the depletion of Nb relative to other HFS-elements suggest involvement of subduction component in the depleted mantle source, and suggest that these rocks were formed in a supra-subduction zone tectonic setting.

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